1. Field of the Invention
This invention relates to a magnetic tape having a leader tape and more particularly, it is concerned with a magnetic tape having at at least one end thereof a leader tape capable of cleaning a magnetic head in a magnetic recording device.
2. Description of the Prior Art
In magnetic recording instruments such as audio cassette recorders or video tape recorders, leader tapes are used in combination with the ends of magnetic tapes so as to clean dirt or dust off the recording and reproducing heads in use and the guide poles or rollers in the running paths.
In the leader tapes of the prior art, it is known to provide a cleaning layer on a support by coating thereon an inorganic pigment such as alumina (Al.sub.2 O.sub.3), silicon carbide (SiC), chromium oxide (Cr.sub.2 O.sub.3), titanium oxide (TiO.sub.2), red oxide (.alpha.-Fe.sub.2 O.sub.3) or silicon oxide (SiO.sub.2) with a binder (Japanese Patent Publication No. 7631/1980).
Such a cleaning layer has a sufficient cleaning ability, but meets with the disadvantage, on the other hand, that the appearance of the cleaning layer varies and the cleaning ability deteriorates after storage at high temperatures. In order to overcome this disadvantage, a matting method has been proposed comprising subjecting the surface of a support to a sand blasting treatment instead of using abrasives (Utility Model Publication No. 4276/1974). However, the surface roughness obtained by this method is limited and this method often results in lowering of the breaking strength of the support.
A method comprising using an inorganic powder and organic powder has been disclosed in Japanese Patent Application OPI (Kokai) No. 12411/1982. According to this method, the leader tape has a good cleaning effect and head protecting effect in use at room temperature, but after storage at high temperatures, it meets with change of the appearance due to partial clarification and deterioration of the cleaning effect.